As we emerge from the (now unfortunately familiar) February deep freeze/polar vortex, it turns the mind towards spring and the growing season. It seems a bit more possible and a bit more real. However, with the almost imminent shift into spring, there is a need to consider tasks that need to be done before plants start to wake up and the rush of the growing season is upon us.
In an orchard, late winter is a time for pruning. Pruning is done for a number of purposes, but late winter pruning is typically focused on clean up and canopy thinning. The effect of specific pruning practices will vary depending the age and maturity of a plant and where you are pruning on the plant.
Pruning Different Plant Types
If you have raspberries, you could remove spent floricanes from your floricane-type (summer bearing) raspberries. You can also thin out excess canes, to open up the canopy and increase air flow. Thinning can also reduce crowding and potential mechanical damage from rubbing. Start by removing spent canes, then assess the density of the remaining canes (floricanes and primocanes).
Primocane-type (fall-bearing) raspberries can be mown down to the ground, as they are going to completely regrow. If you find that the number of canes is excessive or appears crowded, you could remove some to open up the canopy and reduce rubbing.
For woody bush fruits like Saskatoon berries, black currants, and others, the timing of pruning might depend on how easily you can see the base of the plants.
Pruning is done to remove sucker growth and older and larger branches. Pruning suckers will keep the plants closer to a desired density. This allows you to control the width of the row and the spread of the plants. At the same time, this will also improve the flow of air within the canopy.
If you are using a mechanical harvester, row width, plant shape, and plant structure have to be carefully managed so that the harvesters can function effectively and efficiently.
Pruning encourages the plant to establish new growth regularly, which improves plant health and overall plant vigour. This will ensure that there is a good amount of young, fruiting wood. Pruning can help to prevent declining productivity in a planting, as the pruning keep plants young and extends the overall orchard longevity. If you have an older orchard, pruning can rejuvenate it, re-establishing proper plant structure and growth habits. Regular pruning will help to keep plants producing a stable and predictable high yield of fruit each year, rather than having a boom/bust biennial bearing cycle.
In general terms, pruning keeps the canopy open, which will improve plant health, as diseases like stale air, high humidity and anything that might cause wounding or weakening. Pruning out weak, dead, or damaged branches will help to keep plants healthy and prolong the lifespan of plants. It can also prevent or limit the spread of problems within an orchard or plant.
When properly applied, pruning can have a significant impact on the healthy and productivity of individual plants and orchards.
Pruned material should be removed the orchard and disposed of in such a way as is appropriate. If it is mostly healthy plant material, it could be chipped and spread, or might be repurposed in some way. If you are concerned about diseases and pests, burning or burial might be best.
There might be other tasks that can be completed while plants are dormant, and the rush of the growing season is still in the not-too-distant future. Take time to evaluate the overall flow and layout and make any corrections that you can. It is also a time for you to freshen up other elements, such as signage, fences, etc.